Thomas briggs gregory



www. tats THOMAS BRIGGS GREGORY, OF OHAMPAIGN, ILLINOIS.

Letters Patent No. 105,195, dated July 12,1870.

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The Schedule referred to in these Lettera Patent and mah-.ing peut of the same To all whom it may concern Be it known that I, THOMAS Bmces GREGORY, of Champaign, in the county of Champaign and State of Illinois, have invented a new and improved Bridge, and I do hereby declare *hat the following is a. full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the 'accompanying drawing forming part ot' this specification, which represents a perspective View of my improved bridge.

The object of 'this invention is ,improvement in bridges, so constructed as topbe adjusted vertically; and consists in the construction of extension posts, of which the upper parts are secured to the cap, and the lower to the supporting frame or sill of the bridge.

lhe contiguous faces of the sections of posts are notched or toothed to lock into each otherand to thereby be supported in any desired position. Bolts, clamps, and stretchersr may further be used to secure the cap in the desired height.

A A, iu the drawing, are the foundation sills, and B is one of'. the main sills cfa bridge.

C G are thc post-s framed into the sill B, and stayed by longitudinal braces aand lateral brases b.

E E are posts framedinto the cap F, Which-supports the track-stringers G by means of corbels d.

Jackscrews c c are placed between the cap F and the upper ends ofthe posts C. I

The posts E are so applied to the cap that they fit against the posts C, asslxown.

,The contiguous surfaces oi' the posts C E are toothed in such manner that the teeth or notches help supporting the cap. l,

Stretchers H H are interposed between the several posts, tovhold the same well togethenand keys f applied to them, as shown, to make up for shrinkage of the wood.

Clamps D are, by bolts g, secured to the upperends of the posts C, and. other clamps, D', by bolts g', to the lower ends ofthe posts E, to aid in bracing them.

Bymeans of the posts C E the cap can be raised or lowered at will,lto adjust the bridge to the level of the road, however that may be changed. For railroad bridges the invention is of inestimable value.

Having thus described my invention,

1 I claim as new and desire to secure by Letters Patent- Ilhe extension posts C E of abridge, combined with the stretchers H and clamps D D', as set forth.

THOMAS BRIGGS GREGORY.

Witnesses:

H ENnY Tnnvnrr, HALL T. TAYLOR. 

